By early afternoon in Europe, benchmark U.S. crude oil for May delivery was up 90 cents to $101.34 a barrel in electronic trading on the New York Mercantile Exchange. The contract slipped 70 cents on Monday following reports that four Libyan oil terminals under militia control could soon open, possibly boosting global supplies.

Brent crude, used to set prices for international oil varieties, was up 61 cents to $106.43 on the ICE Futures exchange in London. It fell 90 cents on Monday to $105.82.

Tensions in Ukraine escalated again Tuesday, as security forces ousted pro-Russian protesters from an occupied government building in the eastern city of Kharkiv, while regional administration headquarters in Donetsk remained under protesters’ control. They are demanding referendums on the regions’ status, which could pave the way for further annexations by Russia.

“Any further escalation of the situation would intensify tensions between Russia and the West and could lead to tighter sanctions being imposed on Russia,” said analysts at Commerzbank in Frankfurt in a note to clients. “So far, the market appears to believe this to be unlikely, though that means the price would react all the more strongly if sanctions actually were imposed on the Russian oil and gas sector.”

Investors will also be monitoring fresh information on U.S. stockpiles of crude and refined products.

Data for the week ending April 4 are expected to show a build of 2.5 million barrels in crude oil stocks and a draw of 1.3 million barrels in gasoline stocks, according to a survey of analysts by Platts, the energy information arm of McGraw-Hill Cos.

The American Petroleum Institute will release its report on oil stocks later Tuesday, while the report from the Energy Department’s Energy Information Administration — the market benchmark — will be out on Wednesday.

U.S. crude oil and distillates inventories are running at or slightly below levels a year ago.